<em>The word usage in last sentence of the question is not well presented. However, I can understand that you intend to solve for the width of the park</em>
Answer:

Step-by-step explanation:
Given


Required
Determine the Width
For a rectangle:

Substitute for Area and Length

Multiply both sides by 





Answer:A General Note: Rate of Change
The average rate of change between two input values is the total change of the function values (output values) divided by the change in the input values.
Step-by-step explanation: